1. Field of the Invention
Of particular concern in dairy herds is inflammation of the mammary gland referred to as mastitis. Mastitis is an inflammation, which in the acute form results in swelling, redness, heat, pain and loss of function. The majority of occurrence of mastitis are bacterial in origin.
The use of antibiotics has been highly successful in curing and reducing the incidence of mastitis. However, the use of antibiotics has many disadvantages. While antiobiotics have been capable of controlling the incidence of mastitis resulting from Staphylococci and Streptococci infection, the result has been that the effectiveness of the natural protective resistance to other bacterial organisms such as coliform has been diminished. That is, apparently when the immunological system of resistance was stressed by either Staphylococci or Streptococci, this system was able to counteract invasion from other organisms. When antibiotics are employed which destroy the aforementioned organisms, the mammmary gland becomes susceptible to infection from other organisms which are antibiotic resistant.
It is therefore desirable to find ways to induce this immunological and resistance system to protect the host from bacterical invasion.
2. Brief Description of the Prior Art.
U.S. Pat. No. 4,202,329 relates to a method and apparatus for inhibiting bacterial infection by introducing into at least one gland cistern of an udder, a non-toxic non-specific antigenic device of a sufficient size to be restrained from entering the teat cistern of the udder. In said patent, the specifically described device floats in the milk present in the udder. The floating device thus makes intermittent tissue contact within the gland cistern, thus stimulating immune resistance, particularly by inducing an increase in the number and activity of phagocytic cells, particularly leukocyte cells, in the udder.
Although the results obtained with the device as specifically described in U.S. Pat. No. 4,202,329 have been satisfactory, certain minor disadvantages have been associated with such a device. In particular, because the floating device relies upon abrasion of the wall areas of the cistern to stimulate the production of somatic cells, some bleeding has been found to be associated with the abrasion of the cistern wall area. Also, it has been found that after approximately a nine-month period, a biofilm buildup occurs on the device, causing a substantial reduction in the stimulus effect of the floating device. Additionally, the exterior of the floating device which has been used in such a manner, typically has had a rough exterior surface which provided sites for colonization of bacteria, especially when the device was inadvertently placed in an already infected quarter.
An object of the present invention is to obtain the advantages of the device described in U.S. Pat. No. 4,202,329, while overcoming the aforementioned disadvantages thereof.